Contract farming can be defined as an agricultural production carried out according to an agreement between the company and farmers, which establishes conditions for the production and marketing of a farm product or products.
Stevia Hub India is one of those companies who provides a platform for farmers to pursue the agricultural practices to cultivate the land. Stevia plant is cultivated and harvested by them . In return, Company pay them the fair prices according to the total quantity produced by them. The company often also agrees to support the farmer through supplying inputs (seeds, plants), assisting with land preparation, providing production advice and transporting produce to its premises. Contracts with farmers also reduce the risk from disease or weather and facilitate certification, which is being increasingly demanded by advanced markets.
Hence, Contract Farmimg is an effective way to increase the companies production and the financial stability of farmers too.
According to Global Industry Analysis, Artificial Sweeteners, July 2007 Report, International market for sugar free sweetener was of around USD 47.5 billion in 2007-08. Stevia market accounted for only USD 5.5 bn. Opportunity appears great. Statistics indicate that in some countries up to 30% of their needed sugar is replaced by stevioside.
Stevia prefers a well – drained fertile sandy loam or loam soil, high in organic matter with ample supply of water. It prefers acidic to neutral pH 6-7 for better growth. It requires a consistent supply of moisture, but not waterlogged. Too much soil moisture can cause rot.
It is a semi – humid subtropical plant that shows higher leaf production under high light intensity and warm temperature. Day length is more critical. Long spring and summer day’s favors leaf growth. Short days trigger blossoming. Stevia prefers partial shade during considerable summer sunshine.
Stevia is usually propagated by cultivating saplings which are raised separately in a nursery.
Land is either diced and / or harrowed twice to prepare a fairly smooth, firm – planting surface. Around 0.5MT of Organic manure/ acre have to be applied as a basal dressing during the last plough to incorporate the manure with soil. With proper drainage and irrigation channels the field is divided in to plots of convenient size.
Forming raised beds is the most economical way to grow Stevia. The raised bed should be of 15 cm in height and 60cm in width.
The quantity of plants per acre is 35,000 from February to mid-May gives better results. Immediate after planting one Irrigation is necessary. The concentration of stevioside in the leaves increase when the plants are grown under long day condition where vegetative period is longer and steviol glycoside yields will be higher.
It needs irrigation, as Stevia cannot stand drought .Micro sprinkler or Drip irrigation system is highly recommended and have been found to be advantageous since the herb is highly sensitive to water stress and requires frequent light irrigation. During summer, Irrigation at 3-5 days interval gives best results.
In order to reduce the impact of drought and high temperature, addition of mulches around the plant is recommended.
No serious pest and diseases have been observed. Neem oil diluted in water may be sprayed against aphids if appear. Deer and rabbits are fond of Stevia due to sweet taste.
Time of harvesting depends on land type, variety and growing season. The first harvest of the crop can be had in four months after plantation and subsequent harvest once every 3 months. Short days induce flowering. Optimum yield (biomass) and stevioside quality and quantity is best obtained just before flowering. The easiest harvesting technique is to cut the branches off with pruning shears before stripping the leaves. The tips of the stem can be clipped off and added to harvest yield, as they contain as much Stevioside as do the leaves. On an average the commercial harvest can be obtained per year. It is better to cut the plants leaving about 10cm stem portion from the ground. This will facilitate new flushes to emerge, which can be harvested as the next crop.
Immediately after harvest the herb is dried. This can be accomplished on a screen or net. The freshly harvested plants can be hung upside down and dried in shade. It can also be dried using simple drying racks inside transparent poly or transparent glass roofing or by passing dry air just above room temperature. Drying of the stem and soft green leaf material is completed immediately after harvesting utilizing a drying wagon or a kiln or done naturally in case of large scale production. Depending on weather conditions and density of loading, it generally takes 24 to 48 hours to dry Stevia at 400 to 500 C. The drying process does not require excessive heat; more important is good air circulation. On a moderately warm fall day, stevia can be quick dried in the full sun in about 12 hours. Longer drying times will lower the Stevioside content of the final product. A home dehydrator can also be used, although sun drying is the preferred method. After adequate drying, the leaves are stripped of the stems/ twigs and packed and stored in cool, dry place. For large –scale commercial production artificial drying threshing of the dry herbs to separate leaves may be employed.
It gives on an average of about 2.5 to 3.50 tons of dried leaves per acre per year. Then decreases after the fifth year therefore it is advised to renew the cultivation after the fifth year.
From the subsequent years some plants will die off duet to various reasons, these gaps should be immediately filled by well-developed seedlings .Depending upon the soil type and management the productivity will decline after 5 years and this should be replaced with new plantation.